How to make a cool roof or metal material in Honeybee( energy plus engine)

Hi there
I would like to model a cool roof for a building with honeybee , I search every where but I can not find any instruction that, how can I make a metal material for energy plus engine ,I need a construction for roof that upper layer is metal that has characteristics like Emissivity, Reflectance and …

Are you working in the LBT plugin or the Legacy plugin? That will allow us to point you to the right component.

In both plugin versions, you just create a metal material by setting the various properties of an opaque material to be in line with metal.

I am working on the Legacy plugin: is that like a “green roof” material we have to write on a panel component?

No, if there’s no vegetation on the roof, you should just use the “EnergyPlus Opaque Material” component:


If there is vegetation, the way to model it in Honeybee is to create the description string manually as you did here?,0

GreenRoof, !- Name
0.2, !- Height of Plants {m}
1, !- Leaf Area Index {dimensionless}
0.22, !- Leaf Reflectivity {dimensionless}
0.95, !- Leaf Emissivity
180, !- Minimum Stomatal Resistance {s/m}
Green Roof Soil, !- Soil Layer Name
MediumRough, !- Roughness
0.1, !- Thickness {m}
0.35, !- Conductivity of Dry Soil {W/m-K}
1100, !- Density of Dry Soil {kg/m3}
1200, !- Specific Heat of Dry Soil {J/kg-K}
0.9, !- Thermal Absorptance
0.7, !- Solar Absorptance
0.75, !- Visible Absorptance
0.3, !- Saturation Volumetric Moisture Content of the Soil Layer
0.01, !- Residual Volumetric Moisture Content of the Soil Layer
0.1, !- Initial Volumetric Moisture Content of the Soil Layer
Advanced; !- Moisture Diffusion Calculation Method

(Anyone interested, the documentation on Material:RoofVegetation is here.)

If the moisture content is small, e.g. I have an extensive green roof, is it “good enough” to approximate it with an opaque material?

can you give me an example of high reflection metal with the “EnergyPlus Opaque Material” component, please?
(I need this for “cool roof” material which cooling buildings by roof reflection)